Aero and driving mods for Volvo 240 Wagon 34 mpg

[ademonrower]

Car: Volvo 245 GL, late 1979, with B21A gasoline motor (carburetor), 107 bhp, manual transmission with ONLY 4 GEARS!

Latest results (long run): US mpg 34, or UK mpg 41... (6.9 liters/100 km), yes, it is possible

Here are my "physical mods" - see also the uploaded picture:
- Front lip (standard 240 one)
- Sheath going from front lip to the plastic under-engine pan, thus closing most of this gap, and reducing turbulence - made myself
- A-pillar sheaths, made from curved-section PVC, painted and attached via custom fittings under the rubber seal of the windshield, and on a convenient thread-point in the A-pillar itself, where the radio antenna used to be :-)
- Sheath bridging gap between front-edge of gas tank and the front edge of the rear bumper, thereby closing this gap, and reducing significant turbulence because of the bumper. Made of aluminium D.I.Y.
- Flow-extender mounted on the tailgate (tricky D.I.Y., but managed it, and the solution is actually quite easy - advice availabe on request :-) ) This, and the previous, mod probably makes the most difference: extends flow so that turbulence occurs further removed from the back window pane, therefore less suction and hence drag.

Tyres: 185/80 14C, with 3.0 bar pressure

Driving style: long run with mixture of country roads and motorway, always doing pulse and glide where possible, particularly down-hill. Motor still running when gliding, because I don't have a vacuum cylinder mod to charge up for the servo braking, and I can't foresee making one.

Note, all the physical mods are very sympathetic to the classic nature of the car, and really do it a service. The front and back spoilers look so natural that all of the 245s should have been fitted with them :-)

So, whaddya think? :-) Lemme know!

[aerohead]

To the un-trained eye, your color-matched mods will probably pass as 'OEM' structures. And at 34-mpg, the 'old girl' is exceeding the mpg of some current crossover utility vehicles, which have obsoleted the 'station wagon' / 'shooting brake.'
Good for you, good for us!

[Piwoslaw]

Aeromods on a brick - impressive.
Keeping them discreet -priceless

I admire trying to squeeze even more km out of each litre of fuel, especially if you are already doing well.

You seem to be keeping the mods out of sight - Is this because the car has antique status? Or is it to avoid potential problems with police/legalization?


Another mod I would recommend is a grille block. It helps both aerodynamics and improves engine warm-up (and is great when paired with insulation and an engine coolant warmer!).
The grille block can be made clear, and can open/close if you are worried about overheating.

[ademonrower]

Yes, the mods are kept "modest" (ha ha) because the car has historic status (it has an H-number plate). However, I am currently making headlight covers to reduce front-end drag (the headlight/trim assembly is far to "open" for my liking in this early model 245) and protect the glas lenses, and whilst I'm about it, I think I'll make a radiator shield that can be lowered from inside. Outside will surely attract the attention of the inspectors... Thank you for your praise and encouragement! The biggest difference that has still to materialize is the 5-speed Volvo gearbox. I bought it 2nd hand a couple of years ago, but haven't had the time to fit it. If anyone with experience in that area reads this, do let me know :-)

[aerohead]

I ran across a file for CAR and DRIVER's road test of the 1985 Volvo 760 GLE wagon:
Cd 0.41
Af 2.16 meters-square
Curb weight 3236-pounds
205/55VR-16 tires
185-bhp @ 5300 rpm
Road Load @ 30-mph= 6-horsepower
Road Load @ 50-mph= 17-horsepower
Road Load @ 70-mph= 38-horsepower
Top Speed = 127-mph @ 5,000 rpm
EPA City 20 mpg
EPA HWY 26 mpg
C/D observed fuel economy 14 mpg
--------------------------------------------------------------------------------------
The Volvo 740 GLE:
Cd 0.41
Af 2.16 meters-square
--------------------------------------------------------------------------------------
Volvo 360 GLT:
Cd 0.41
Af 1.95 meters-square

[ademonrower]

Interesting that all Volvos actually have great scope for fuel reductions, meaning that the redblock engines aren't so bad after all, particularly because they can all be driven at low rpm.

[ALS]

I modded my old 87 740 Turbo Wagon with a 2.3 Liter Redblock. At 65 mph it would get 325-330 miles per tank 60L/15.8 gal stock, 430-440 miles per tank afterward. Mods, IPD lowering springs, bigger sway bars with Bilstein struts and shocks, replaced the 15 inch Alloy wheels with 16 inch 940 Hydra's. Pulled the AW71 automatic and swapped in a M46 5 speed manual and replaced the rear gears from 3.91 down to 3.31's. Took off the roof rack and had the holes filled. Most of my gains were from two areas, Aero, lowering and removing the roof rack, and drive train efficiency which lowered the RPMs at higher speeds. Also going from 15 inch to 16 inch wheels dropped the number of rotations of the tire at any given speed.

She also was modified for more power. I added a Saab APC boost controller off a 900 so I could increase the boost and control it from the driver seat. Rocker switch powered off I was running stock 7 psi. Flip the switch and put power to the APC controller I had 12.5 psi available. Stock 160 HP vs around 200 HP with the APC on. At 65 mph it ran around 1850 RPM's. Original stock it ran around 2200 RPMs. One thing that killed the mileage in the 200,700 and 900 Turbo automatics was non of them came with a locking torque converter. That's why the 91-93 940's non turbos with locking torque converters could get 32-33 mpg on the highway.

[ademonrower]

Very impressive improvement in mpg! Particularly for a turbo. Indeed, the non-locking torque converters in the earlier Volvo auto trans was a great fuel waster. In general, even with a torque converter lock, a manual is still by far the better choice for mpg improvements. I reckon that I could even beat a very modern auto with an identical manual and pulse-glide driving style and looking far ahead. But it's all more work for the driver :-) Still, if cognitive psychologists are right, there seems to be a positive connection between driving a stick shift car and delayed onset and lower severity of Alzheimer's: at least I read a couple of research papers along those lines. I don't rule out the converse connexion between the two things, but I'd rather not take the risk, so I drive my stick shift car with the knowledge that I am using my brain, taking responsibility for driving, and not finding it so pleasant that I am tempted to drive too much :-) We could start a thread on automation of everything and how it leads people to give up responsibility for things, and stop using their brains, but that thread would doubtless be provocative in a destructive way, so I'll keep the ideas to myself and my own personal practices :-)

[Piotrsko]

Alzheimer's seems to be related to heredity AND lack of significant daily challenge to the thought process. Currently cant do anything about heredity, CAN over drug the subject suppressing symptoms, leaves only mental stimulation as a preventive.